Answer:6.5
Explanation:
Angle C is 90° therefore we can apply Pythagoras principle to get the diameter Of The circle
Diameter=√(12^2+5^2)
Diameter=√(12x12+5x5)
Diameter=√(144+25)
Diameter=√(169)
Diameter=13
Radius=diameter ➗ 2
Radius=13 ➗ 2
Radius=6.5